Which expression is not a polynomial?

А. 8 х^10 + 2 х^5

B. 5 х^5

C. x^5+2

D. 5 х^-1 + 4 х^-2

D.

Step-by-step explanation:

A term in a polynomial is a single number or a number multiplied by any number of variables. A polynomial is a sum of terms.

The only thing that can be done with variables in a polynomial is to multiply them by numbers or other variables. In a polynomial, you cannot: divide by a variable (have a variable in a denominator), have a root of a variable, have a log of a variable, have a variable as an exponent, etc.

All expressions are polynomials except for D. In D., the negative exponents mean division by variables.